Ice in the California Desert Brings Frost Damage

Weather can be rough in the California desert growing regions. Last week the Coachella and Imperial Valleys experienced 3 days of ice with temperatures dipping into the low 30’s. This is at a point in the season where warm weather veg has already been planted in the California desert. We are seeing frost damage mainly on romaine and leaf lettuce. Epidermal peel occurs when the outside ribs of the lettuce freeze, bubble, pop and finally oxidize. Fringe burn damage happens when the edges of the lettuce turn brown from the cold. This is more evident on leaf lettuce because it is not as coarse as romaine leaves. The damage shows up more easily on green leaf lettuce while the darker color of the red leaf lettuce makes it much harder to see. An overall “rough” appearance is to be expected on lettuce for the next 2-3 weeks.

Frost damage occurs as a result of a combination of things; the actual temperature, the duration of that temperature, the soil moisture and the age of the plants. Some crops, like kale, can freeze solid, thaw out and be fine; this process can happen multiple times and the kale will actually become sweeter. For other crops, one event below 32 degrees is basically a killing frost for that item. Summer squash and tomatoes are very good examples of cold sensitive crops.

The California desert and Yuma wet veg crops are just in the beginning of harvesting from the first plantings and supply still seems strong. February is only a few days away and for those of us living in California we are very spoiled with most produce only a 1-2 day ride away. In a few weeks Salinas will be coming on briefly with Cauliflower and Broccoli planted back in November during a break in the weather. There will be a short period where two growing regions will overlap with each other. Read Earl’s Weekly Buyer’s Notes for all your produce updates. If you are not on the mailing list talk to your Earl’s Sales Rep or follow us on social media.